וַיִּשְׁמַ֥ע אֱלֹהִ֖ים אֶל־לֵאָ֑ה וַתַּ֛הַר וַתֵּ֥לֶד לְיַעֲקֹ֖ב בֵּ֥ן חֲמִישִֽׁי׃
하나님이 레아를 들으셨으므로 그가 잉태하여 다섯째 아들을 야곱에게 낳은지라
Rashi on Genesis
וישמע אלהים אל לאה AND GOD HEARKENED UNTO LEAH —for she eagerly desired and sought means to increase the number of the tribes (Genesis Rabbah 72:5).
Sforno on Genesis
וישמע אלוקים אל לאה, because she had used both natural means, and then, failing to succeed, relied on prayer. She herself is on record as confirming this when she said נתן אלוקים שכרי אשר נתתי שפחתי לאישי, “G’d has given me my reward for having offered my handmaid to my husband. Giving Zilpah to Yaakov was considered by her as a way of relying on natural means of having more children, seeing she had come to the conclusion that she could not have any more from her own womb.
Or HaChaim on Genesis
וישמע אלוקים, G'd heard, etc. This means that Leah prayed to G'd first.